New research on menopause and calcium supplements.

Calcium supplements—unlike calcium-rich foods, such as milk—increase blood calcium levels for a few hours after they’re taken, says Ian Reid, M.D., the study’s lead author. This bump may raise risk of heart disease—possibly because the calcium is deposited in the walls of the arteries, making them less pliable.

Other experts think women’s supplement habits shouldn’t change, in part because there’s research to show calcium may help the heart. “Postmenopausal women given calcium supplements had a slightly lower risk of stroke and heart disease,” says Robert Heaney, M.D., professor of medicine at Creighton University and an internationally recognized calcium expert, citing a study he and colleagues conducted.